FR 2 696 049 discloses a locking collar provided with weighted locking means. The locking collar is integral with a first electrical connecting element, and is provided with a female thread designed to interact with a male thread of a second complementary electrical connection. The weighted locking means comprise teeth that are asymmetrical in shape. The teeth of the weighted locking means interact with teeth of the second electrical connecting element that are also asymmetrical in shape. The weighting is provided using teeth, for each of the toothings, that are slightly inclined in the direction of screwing and are highly inclined in the direction of unscrewing in relation to the circumferential direction. During screwing, the respective toothings abut against each other until a final position is reached in which the connecting elements and the locking collar are totally immobilized. This total immobilization is obtained when the threaded sections have been screwed as far as possible. The presence of these weighted locking means considerably increases the torque to be applied in order to unscrew the collar whilst maintaining a low screwing torque in order to be able to screw this collar on easily.
However, the screwing means of the prior art suffers from the disadvantage that a constant locking and unlocking force is required throughout screwing.